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Bis(triphenylphosphine)-ethylene-nickel and Analogous Complexes.

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A combination of plant materials, discussed in ancient
Indian medical literature, blocks the estrogen-induced
increase in enzyme activity [172]. Experiments with mice
have shown that nidation can also be prevented by upsetting the endocrine equilibrium needed for this process [173]. Induction of unphysiological motility of the
genital tract before nidation has occurred greatly decreases the viability of the embryo (cf. Table 5).
The question remains whether the anaerobic metabolism
which prevails at the beginning of the second regulatory cycle
and which provides an optimum milieu for fertilization can
be affected in any way. This in turn would modify some of the
functions in the female genital tract needed to effect conception; for example, the production of antiagglutinins and“fertilisins” needed for capacitation of the sperm might be affected.
It has been possible to produce an antigen from sperm
and also antiserum against spermatozoa of different
species [174].
It is not yet possible to foretell the practical significance
of the many measures discussed in this article. As yet
there is competition on the one hand between contraceptive measures that interfere with certain of the mechanisms of conception and mechanical devices, and, on
the other, between these and attempts t o determine the
nonfertile period in the second regulatory cycle (e.g. by
means of the Knaus and Ogino calendar, by measuring
the vaginal temperature in the morning in order to determine the postovulatory rise in temperature caused by
progesterone, or by pregnanediol determination according to Reimann - Hunziker and Wild [175]). On
the basis of statistics, it can be asserted that, when
properly used, gestagens that inhibit the sex center and thereby prevent ovulation have the greatest
contraceptive potentialities and reliability (practically
100 %).
Received, January 24th. 1962 [A 225/47 IE]
[I721 H . S. Chakravarti, J. Indian med. Assoc. 37,322 (1961).
11731 H. M . Bruce, J. Reprod. Fertility 2, 138 (1961).
[I741 A . S.Parkes, J. Reprod. Fertility 3, 158 (1962).
[I751 R . Reimann-Hunziker and W Wild,Med. Klinik 57, 440
(1962).
COMMUNICATIONS
Anionic Heterosiloxanes [ l l
By Dr. H. Schmidbaur and Prof. Dr. Max Schmidt
Institut fiir Anorganische Chemie
der Universitat Marburg/Lahn (Germany)
The siloxyl groups forming coordination bridges between
two metal atoms in the dimeric tris-trimethylsiloxy compounds (I) of Al and Ga [2] account for the great readiness
with which these compounds add on metal siloxides (11).
Even at room temperature, equimolar mixtures of solutions
of { [(CH3)3SiOl3A1}2 or { [(CH3)3SiO]3Ga)z and NaOSi(CH&
or KOSi(CH3)3 in CC4 yield white precipitates of the
sodium or potassium tetrakis-trimethylsiloxy-alanates (111)
or -gallanates (IV) in an exothermic reaction, e.g.
SiR,
RsSi
I
‘o\AI/o\A,/o
/ \o/ \o
RaSi/ O
S~R,
I
PR3
+ 2 R,SiOeM@ 4
'Sib
(11)
(1)
(M = Na or K ; R = CH3). These sodium and potassium salts
are insoluble in organic solvents, and begin to decompose
slowly at temperatures above 250 “C. Their infrared spectra
in Nujol show bands, whose positions prove the existence of
discrete anions (v Si-0-A1 at 10.35 p and v Si-0-Ga at
10.80 p). Analogously prepared lithium salts are soluble in
organic solvents, are fusible, sublime in vacuo, and have
infrared spectra unlike those of the Na and K salts. The
spectra of the Li compounds indicate a strong homopolar
linkage of the metal to the anion, as well as the presence
of molecular association, which is further confirmed by
molecular weight determinations. The proton magnetic
Angew. Chem. internat. Edit. / Vol. I (1962)/ No. 10
resonance spectra in CC4 show only one sharp resonance
singlet, which is an impressive proof of the equivalence of all four siloxyl groups (chemical shift for
Li(Al[OSi(CH3)3]4),-0.125 ppm; for Li(Ga[OSi(CH&I4),
-0.165 ppm [3].
The anions of 111 and IV are isosteric with the neutral siloxanes Si[OSi(CH3)3]4 and Ge[OSi(CH3)314, for example:
R3Si
/SIR3
‘0
\cia/’
\o
- R3Si/O
‘SiR3
(JW
I‘
R3Si
PiR3
O
\
and
\Ge/O
/
R3Si/ O
\o
‘SiR,
B.p. 59-6O0C/1 mm.; m.p. -59°C [41
Their infrared and proton magnetic resonance spectra show
the complete structural identity of the tetrahedral ionic and
neutral siloxane compounds. With analogous “complex
silicones”, where iron was the heteroatom, we obtained
similar results [l].
Received, June 22nd. 1962
[Z 305/139 IE]
[I] Heterosiloxanes,Communication X.-Communication IX : H.
Schmidbaur and M . Schmidt, J. Amer. chem. SOC.,in press.
[2J H. Schmidbaur and M . Schmidt, Angew. Chem. internat.
Edit. I, 328 (1962).
[3] Varian A 60 (60 Mc); solutions of all substances in CC14 at
c = 5 i 1%, with tetramethylsilaneas internal standard.
[4] First prepared by us from GeC14 and four moles of
NaOSi(CH3)s in anhydrous ether.
Bis(tripheny1phosphe)-ethylene-nickel
and Analogous Complexes
By Priv.-Doz. Dr. G. Wilke and Dip1.-Chem. G. Herrmann
Max-Planck-Institut fur Kohlenforschung
Mulheim/Ruhr (Germany)
By the interaction, at approx. 20 “C,of nickel acetylacetonate
with (CzH&AIOC2Hs in the presence of triphenylphosphine
(TPP) (Ni: P = 1 :2) in benzene, bis(tripheny1phosphine)ethylene-nickel, (TPP)ZNi.C2H4) is produced in yellow
549
crystalline form in a yield of about 75 % [I]. Gaseous
reaction products are a little ethylene, but chiefly ethane and
hydrogen. Therefore, the reduction proceeds, at least partially, as follows:
Nickel(0)-dialkylcyanamide-carbonyl
(CsH70z)
Institut fur Anorganische Chemie
der Universitat Miinchen (Germany)
a) Ni(CsH702)z
Ni(C2HS)z
NiHz
By Dr. H. Bock
/
+ 2 AI(CZHS)ZOCZHS+ Ni(CzH5)z + 2 A1-0C2Hs
-
NiHz
+
\
+ 2 CzH4
CzHs
N i + Hz
The evolution of ethane may arise from a side reaction
hydrogenation of ethylene or from radical formation by decomposition of the intermediate Ni(CzH& :
The yield of (TPP)zNiC2H4 can be raised to 90-95 % if a
solution initially saturated with ethylene is employed. Molecular weight determinations in benzene showed that the
compound is monomeric in solution, i.e. it behaves again as
a nickel complex of coordination number 3 [2]. Similarly, the
following compounds (R3P)zNi.C2H4were prepared :
R
I Yield [%I 1 Form
Ethyl
Cyclohexyl
I
I
70
92
Yellow oil
Yellow crystals
Nickel(0)-dialkylcyanamide-carbonyls (1) are formed by the
reaction of dialkylcyanamides with an excess of Ni(C0)4
as analytically pure, air-sensitive orange coloured crystals:
Ia, R = CH3, Decompn. pt. 98'C; Ib, R = -(CH2)5-.
Decompn. pt. 118 "C.
(1)
The structure follows from elemental analysis, molecular
weight determination, diamagnetism and infrared spectra [I]
between 2300 and 1700 cm-1. There are three equally strong
bands (la: 2037(a), 2004(b), and 1790(c) cm-1; Ib: 2037(a),
1980(b), and 1790(c) cm-1). These bands can be attributed to
the N-C-N
skeleton, the vibrations of which are shifted to
lower frequencies by complex formation (a and b), and to the
bridge carbonyl group (c). The nitrile bands of the free
cyanamides occur at 2217 cm-1
An additional confirmation of the proposed structure is
provided by the quantitative thermal decomposition at
10-4 mm Hg :
[Ni(RzNCN) (CO)]z + 2 N i
+ 2 RzNCN + 2 CO
Received, August 1st. 1962
Yellow, crystalline compounds.
Ethylene is expelled by the action of other electron donors.
By volumetric determination of ethylene the progress of the
expulsion can be followed. In all cases over 90 % of ethylene
are obtained.
By splitting-off ethylene from (TPP)2NiC2H4 according to
the general equation:
c) (TPP)zNiGH4
+ Donor + (TPP)zNi.Donor + C2H4
the following crystalline compounds were obtained among
others:
[Z 320/164 IEI
[l] For a discussion of the infrared spectra I am indebted to Dr.
H. P. Fritz; the magnetic measurements were carried out by
cand. phys. H. M6dI, Physikalisches Institut der Technischen
Hochschule Miinchen.
The Intermediate Product of the Wackenroder
Reaction
By Prof. Dr. P.W. Schenk and cand. chem. W. Kretschmer
Institut fur Anorganische Chemie
der Freien Universitat Berlin (Germany)
According to present concepts the treatment of H2S with SO2
in aqueous medium results in two simultaneous reactions:
1)
2)
88 %, yellow orange
The formation of the different polythionic acids can be
interpreted by the equation:
I
3)
90 %, yellow, crystallizes
with 1 molecule of benzene
Investigations are in progress on the infrared and proton
resonance spectra of the described new compounds to
determine the effect of different donors on the bond between
nickel and the CCC multiple linkages.
Received, July 27th. 1962
[Z 316/150 IE]
11) Previously, this compound was erroneously considered to be
[(C~HS)~P]~N~(O):
G. Wilke, E. W. Miiller, and M. Kroner, Angew.
Chem. 73, 33 (1961).
[2] G. Wilke, Angew. Chem. 72, 581 (1960).
550
+
83 %, dark red
C6Hs
60 %, yellow
2 H z S + SO2 + 3 S + 2 H 2 0
HzS 3 SO2 + H2S4O6 (HzS,06)
+
H~S40.5 HzSOJ
+ H2S3Os + HzSzO3
Whereas it is generally accepted that equation 3 is valid,
opinions regarding the initial reactions differ [I]. Since a
major role is sometimes attributed [2] to the sulphur formed
according to equation 1, we tested whether it is in fact
elementary sulphur that precipitates in the reaction of H2S
with SOz. The remarkable golden-yellow colour of the
precipitate could be due to polysulphur oxides [3,4], although monomeric S20 is extremely sensitive to water [5].
We passed H2S into an ice-cold solution of sulphurous acid
to which some NaCl and HCl had been added to permit a
ready flocculation. The golden-yellow precipitate was sucked
off quickly and dried in high vacuum. It was then decomposed
it by quick heating. The abundantly evolved gases, which
were pumped off, condensed in liquid air to a cherry red
condensate. The ultraviolet spectrum of the gases showed
the bands of S20.
Angew. Chem. internat. Edit. 1 Val. I (19621 / No. I0
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